It seems the inevitable is due to take place very soon. By the looks of it I have to think of replacing the piston, rings and the valve guides on the motor. For being such an old motor, I needs some guidance where to start with replacement parts for it.

What piston ring set will suit the motor and what to do about valve guides for the valves?

I would appreciate suggestions as I have entered in the centenary 100 year rally from Johannesburg to Durban on the 7th of March 2013 which is around the corner and would like to have the motor in good shape for it.
Regards
Geno